code: def test_iter(self) -> None:
      it = iter(_TestGroup)
      assert next(it) == named.red
      assert next(it) == named.green
      assert next(it) == named.blue
  
file_path: bokeh/tests/unit/bokeh/colors/test_util__colors.py
imports: from __future__ import annotations
  import pytest
  from bokeh.colors import named
  import bokeh.colors.util
label_desc: Use image node_id 2 for calling the Test_ColorGroup obj's underlying member method code with example usage: obj.test_iter() without return types